I think Allard probably goes down when Walker comes back. Marte or Phillips would be in danger when Ranger is ready.
It feels like Turnbull would not be ready until September as his rehab clock has not even started yet. And Dylan Covey is also a September option as his rehab got transferred to AAA this week. Note they started his rehab in Clearwater on 7/28 so they'll actually have to make a decision on him before September (though if they lost him on waivers in late August it just means they decided others are better).
It just depends how badly they want to run this six-man thing. Originally they wanted it for this road trip but Ranger's injury messed that up. And now it sounds like he still might be a couple of weeks away - maybe not even ready for the trip to Atlanta.
Honestly, after this past week, that late August stretch doesn't loom as large as it once did. They can afford to not push their best pitchers too hard. Though I suppose I would not run a six-man with Walker, Allard and Phillips all in the rotation.
Hard to see Covey sneaking back onto the roster if everyone is healthy. He'd still be behind Turnbull. Phillips has options at least yeah?
All it takes is an injury or Covey pitching well. Obviously the Phillies got him to AAA pretty quickly to see what they have. It might be nothing, it might be something. We'll have to play some games to find out. And we get a 14th pitcher in September so there is lots of room for some back and forth. If everyone were perfectly healthy Covey would probably have made the team out of Spring Training ahead of Marte and Ruiz and Phillips and Allard.
Like I said, if everyone is healthy. None of those people you listed were on the opening day roster. if memory serves Ortiz was supposed to take the last spot and then he got hurt. Brogdon and Pinto were next. For sure if they want him in the mix they will find someone to option before the extra spot opens. Or they could ditch Ruiz.
I thought Ortiz got hurt late in spring training. Agreed Covey probably makes it if he's healthy and so is Walker but it wasn't a sure thing, especially if Turnbull had refused his option.
At this point it hardly matters, they'll all get a chance to soak up some innings, and I guess several of them (Ruiz, Covey, Turnbull, Walker, Phillips) are competing for the playoff spot Lorenzen took last year. In theory Banks is firmly the #6 because he's left-handed. Walker was the #8 last year and of course didn't get in a game. I presume in the first round they will still carry an extra hitter.